This is pretty easy.

1.Mount with Daemon Tools or a similar software.
2.Install and use any of these cd-keys.

EKBD7-BNG9Y-BBDE9-PGER2

XHGLB-VLMLA-BBHM6-CVZTX

EPPPW-KTH8G-BANDU-N397J

Q6AG4-XFVKN-AZ8N2-K7CKU

Q838B-DVQ3M-BECMT-WVCJB

G6E83-YB7AF-BER9D-TQEBK

XLCYB-YB2JW-AX3A3-CR8VU

ZRGJ3-BJAZA-A2JNW-GUFE9


3.Copy Crack from CD1/Crack/UT2003.exe to your UT2003 Directory.